Partitioned backlight display method of red, green, blue, and white (RGBW) display device

• US 10,629,140 B2
• Filed: 09/11/2017
• Issued: 04/21/2020
• Est. Priority Date: 07/14/2017
• Status: Active Grant

• Current Assignee: Wuhan China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Original Assignee: Wuhan China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Inventors: Zha, Guowei
• Primary Examiner(s): Boddie, William
• Assistant Examiner(s): Gyawali, Bipin
• Application Number:
  US15/574,360
• Publication Number:
  US 20190221171A1
• Time in Patent Office: 953 Days
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0271 Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2320/0686 with two or more screen areas displaying information with different brightness or colours
• CPC Class Codes: G09G 2340/06 Colour space transformation
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127

Abstract

The present invention provides a partitioned backlight display method and device of a red, green, blue, and white (RGBW) display. Converting the RGB display to the RGBW avoids problems of pure color darkness from different pixel gain inconsistencies, independently sets saturation gain value in different partitions based on specific screens, and maximizes and enhances penetration rate of W sub-pixel brightness gain effect.

Claims

1. A partitioned backlight display method of a red, green, blue, and white (RGBW) display device, comprising:

dividing a red, green, and blue (RGB) image into a plurality of image partitions based on a backlight partition setting information according to display content on a screen of the display device, each image partition comprising a plurality of RGB pixels;

obtaining a gray scale value of each RGB pixel and converting the gray scale value to a hue, saturation, and value (HSV) space to obtain a saturation of the RGB pixel;

determining each of the RGB pixels being a high-purity color RGB pixel or a non-high-purity color RGB pixel based on the saturation and generating a determining result;

obtaining a saturation gain corresponding to each of the RGB pixels when each RGB pixel is pre-converted into a RGBW pixel;

obtaining a corrected target saturation gain by correcting the saturation gain of each RGB pixel based on the determining result and a visual luminance gain coefficient of each RGB pixel;

setting a saturation gain threshold corresponding to each image partition ,and performing an optimization process on the target saturation gain for each RGB pixel in the image partition based on the saturation gain threshold;

obtaining a gray scale value of the RGBW pixel by converting the RGB pixel into an RGBW pixel according to the target saturation gain after the optimization process;

obtaining a target backlight luminance gain coefficient based on the gray scale value of each RGBW pixel in the image partition and the saturation gain threshold corresponding to the image partition and outputting the target backlight luminance gain coefficient to the backlight drive unit to light the backlight of the corresponding image partition;

obtaining a gray scale compensation screen of the image partition based on the target backlight luminance gain coefficient of the image partition and the gray scale value of the RGBW pixel in the image partition; and

controlling and displaying an image on the screen of the display device based on the gray scale compensation screen of each the image partition.

2. The partitioned backlight display method of the RGBW display device of claim 1, wherein the step of obtaining a target backlight luminance gain coefficient based on the gray scale value of each RGBW pixel in the image partition and the saturation gain threshold corresponding to the image partition comprises:

setting the backlight luminance gain coefficient in the image partition based on the gray scale value of the RGBW pixel in the image partition; and

obtaining the target backlight luminance gain coefficient by correcting the backlight luminance gain coefficient in the image partition based on the saturation gain threshold.

3. The partitioned backlight display method of the RGBW display device of claim 2, wherein the step of performing an optimization process on the target saturation gain for each RGB pixel in the image partition based on the saturation gain threshold comprises:

adjusting the target saturation gain of the RGB pixel to the corresponding saturation gain threshold when the target saturation gain of the RGB pixel of the image partition is more than the corresponding saturation gain threshold.

4. The partitioned backlight display method of the RGBW display device of claim 1, wherein the step of obtaining a corrected target saturation gain by correcting the saturation gain of each RGB pixel based on the determining result and a visual luminance gain coefficient of each RGB pixel comprises:

obtaining a visual luminance gain coefficient x of each RGB pixel;

the target saturation gain of the RGB pixel has n=mx, when the RGB pixel is a high-purity color RGB pixel;

the target saturation gain n=m, when the RGB pixel is a non-high-purity color RGB pixel; and

wherein, m is the saturation gain of the RGB pixel.

5. The partitioned backlight display method of the RGBW display device of claim 1, the step of obtaining a gray scale value of each RGB pixel and converting the gray scale value to a HSV space to obtain a saturation of the RGB pixel comprises:

normalizing the RGB pixels and obtaining a gray scale values of the normalized RGB pixels; and

obtaining the saturation of the RGB pixel by converting the gray scale value of the RGB pixel to the HSV space.

6. A partitioned backlight display device for RGBW displaying, comprising:

a processor configured to execute computerized code to perform a method, the method comprising;

dividing a red, green, and blue (RGB) image into a plurality of image partitions based on a backlight partition setting information according to a display content on a screen of the display device, each image partition comprising a plurality of RGB pixels;

obtaining a gray scale value of each RGB pixel and converting the gray scale value to a hue, saturation, and value (HSV) space to obtain a saturation of the RGB pixel;

determining each of the RGB pixels being a high-purity color RGB pixel or a non-high-purity color RGB pixel based on the saturation and generating a determining result;

obtaining a saturation gain corresponding to each of the RGB pixels when each RGB pixel is pre-converted into a RGBW pixel;

obtaining a corrected target saturation gain by correcting the saturation gain of each RGB pixel based on the determining result and a visual luminance gain coefficient of each RGB pixel;

setting a saturation gain threshold corresponding to each image partition ,and performing an optimization process on the target saturation gain for each RGB pixel in the image partition based on the saturation gain threshold;

obtaining a gray scale value of the RGBW pixel by converting the RGB pixel into an RGBW pixel according to the target saturation gain after the optimization process;

obtaining a target backlight luminance gain coefficient based on the gray scale value of each RGBW pixel in the image partition and the saturation gain threshold corresponding to the image partition and outputting the target backlight luminance gain coefficient to the backlight drive unit to light the backlight of the corresponding image partition;

obtaining a gray scale compensation screen of the image partition based on the target backlight luminance gain coefficient of the image partition and the gray scale value of the RGBW pixel in the image partition; and

controlling and displaying an image on the screen of the display device based on the gray scale compensation screen of each the image partition.

7. The partitioned backlight display device for RGBW displaying of claim 6, wherein the step of obtaining a target backlight luminance gain coefficient based on the gray scale value of each RGBW pixel in the image partition and the saturation gain threshold corresponding to the image partition and outputting the target backlight luminance gain coefficient to the backlight drive unit to light the backlight of the corresponding image partition comprises:

setting the backlight luminance gain coefficient in the image partition based on the gray scale value of the RGBW pixel in the image partition; and

obtaining the target backlight luminance gain coefficient by correcting the backlight luminance gain coefficient in the image partition based on the saturation gain threshold.

8. The partitioned backlight display device for RGBW displaying of claim 7, wherein the step of setting a saturation gain threshold corresponding to each image partition ,and performing an optimization process on the target saturation gain for each RGB pixel in the image partition based on the saturation gain threshold comprises:

setting a saturation gain threshold corresponding to each image partition; and

adjusting the target saturation gain of the RGB pixel to the corresponding saturation gain threshold when the target saturation gain of the RGB pixel of the image partition is more than the corresponding saturation gain threshold.

9. The partitioned backlight display device for RGBW displaying of claim 6, wherein the step of obtaining a corrected target saturation gain by correcting the saturation gain of each RGB pixel based on the determining result and a visual luminance gain coefficient of each RGB pixel comprises:

obtaining a visual luminance gain coefficient x of each RGB pixel;

setting the target saturation gain of the RGB pixel to mx, when the RGB pixel is a high-purity color RGB pixel;

a third setting unit for setting the target saturation gain to m when the RGB pixel is a non-high-purity color RGB pixel; and

wherein, m is the saturation gain of the RGB pixel.

10. The partitioned backlight display device for RGBW displaying of claim 6, wherein the step of obtaining a gray scale value of each RGB pixel and converting the gray scale value to a hue, saturation, and value (HSV) space to obtain a saturation of the RGB pixel comprises:

normalizing the RGB pixels and obtaining a gray scale values of the normalized RGB pixels; and

obtaining the saturation of the RGB pixel by converting the gray scale value of the RGB pixel to the HSV space.

11. A partitioned backlight display device for RGBW displaying comprising:

a processor configured to execute computerized code to perform a method, the method comprising;

dividing a red, green, and blue (RGB) image into a plurality of image partitions based on a backlight partition setting information according to a display content on a screen of the display device, each image partition comprising a plurality of RGB pixels;

obtaining a gray scale value of each RGB pixel and converting the gray scale value to a hue, saturation, and value (HSV) space to obtain a saturation of the RGB pixel;

determining each of the RGB pixels being a high-purity color RGB pixel or a non-high-purity color RGB pixel based on the saturation and generating a determining result;

obtaining a saturation gain corresponding to each of the RGB pixels when each RGB pixel is pre-converted into a RGBW pixel;

obtaining a corrected target saturation gain by correcting the saturation gain of each RGB pixel based on the determining result and a visual luminance gain coefficient of each RGB pixel;

setting a saturation gain threshold corresponding to each image partition, and performing an optimization process on the target saturation gain for each RGB pixel in the image partition based on the saturation gain threshold;

obtaining a gray scale value of the RGBW pixel by converting the RGB pixel into an RGBW pixel according to the target saturation gain after the optimization process;

obtaining a target backlight luminance gain coefficient based on the gray scale value of each RGBW pixel in the image partition and the saturation gain threshold corresponding to the image partition and outputting the target backlight luminance gain coefficient to the backlight drive unit to light the backlight of the corresponding image partition;

obtaining a gray scale compensation screen of the image partition based on the target backlight luminance gain coefficient of the image partition and the gray scale value of the RGBW pixel in the image partition; and

controlling and displaying an image on the screen of the display device based on the gray scale compensation screen of each the image partition;

wherein the step of obtaining a target backlight luminance gain coefficient based on the gray scale value of each RGBW pixel in the image partition and the saturation gain threshold corresponding to the image partition and outputting the target backlight luminance gain coefficient to the backlight drive unit to light the backlight of the corresponding image partition comprising;

setting the backlight luminance gain coefficient in the image partition based on the gray scale value of the RGBW pixel in the image partition; and

obtaining the target backlight luminance gain coefficient by correcting the backlight luminance gain coefficient in the image partition based on the saturation gain threshold;

wherein the step of setting a saturation gain threshold corresponding to each image partition ,and performing an optimization process on the target saturation gain for each RGB pixel in the image partition based on the saturation gain threshold comprising;

setting a saturation gain threshold corresponding to each image partition; and

adjusting the target saturation gain of the RGB pixel to the corresponding saturation gain threshold when the target saturation gain of the RGB pixel of the image partition is more than the corresponding saturation gain threshold;

wherein the step of obtaining a corrected target saturation gain by correcting the saturation gain of each RGB pixel based on the determining result and a visual luminance gain coefficient of each RGB pixel comprising;

obtaining a visual luminance gain coefficient x of each RGB pixel;

setting the target saturation gain of the RGB pixel to mx, when the RGB pixel is a high-purity color RGB pixel;

setting the target saturation gain to m when the RGB pixel is a non-high-purity color RGB pixel; and

wherein, m is the saturation gain of the RGB pixel; and

wherein the step of obtaining a gray scale value of each RGB pixel and converting the gray scale value to a hue, saturation, and value (HSV) space to obtain a saturation of the RGB pixel comprising;

normalizing the RGB pixels and obtaining a gray scale values of the normalized RGB pixels; and

obtaining the saturation of the RGB pixel by converting the gray scale value of the RGB pixel to the HSV space.